1. Field of the Invention
The invention relates to hexapeptide amides which are useful as Substance P agonists and/or antagonists and are therefore useful as analgesics and/or as antihypertensives.
2. Information Disclosure Statement
Substance P (SP) is an endogenous undecapeptide amide and a putative neurotransmitter of mammalian central nervous systems (Sandberg et al., J. Med. Chem., vol. 25, no. 9, pp. 1009-1015, 1982) having the following structural formula, wherein the amino acid units are numbered from 1 through 11 beginning with the N-terminal amino acid: ##STR1## The hexapeptide amide having the structural formula ##STR2## is referred to as SP.sub.6-11.
Chorev et al. (Peptides 1980, Proceedings of the Sixteenth European Peptide Symposium, Helsinger, Denmark, August 31-September 6, 1980 Edited by K. Bunfeldt, Scriptor, Copenhagen, 1981, paper entitled "Spatial Requirements at the N-Acylating Residue of Substance P Partial Sequence", pp. 451-456) describes as SP Analog No. 13 in Table 1 at page 455 [Pro.sup.6 ]SP.sub.6-11, which is SP.sub.6-11 wherein L-glutaminyl at position 6 is replaced by L-prolyl.